This invention relates to improvements in interfolding machines in which webs of paper are interfolded into bundles which can be severed into appropriate lengths for facial tissues or other sanitary products.
Facial tissues are conventionally packaged in an interfolded relation, so that as one tissue is removed from its container, the succeeding tissue will be raised to an accessible position, and so on. Machines for interfolding webs of tissue are well known, as can be evidenced by Marcalus et al U.S. Pat. No. 3,850,425, dated Nov. 26, 1974. The Marcalus et al patent is particularly unique for its disclosure of a highly simplified and compact mechanism for interfolding webs of tissues, and this disclosure is incorporated by reference as if set forth at length herein. The present invention is an improvement thereon.
In accordance with principles disclosed in the Marcalus et al patent, roll-wound webs of tissue paper are arranged in a semi-circular array, with the webs converging to a central conveying mechanism. Folding assemblies are deploying to interfold adjacent webs as the webs are pulled by an approach the conveyor structure. Consequently, there is formed by the machine a bundle of interfolded webs of tissue paper. This web bundle is subsequently cut into stacks of appropriate lengths and a plurality of such stacks can be packaged in a typical slotted tissue container. As each tissue is withdrawn from the container, the succeeding tissue, due to its interfolded connection with the previous tissue, is lifted to an accessible position for subsequent withdrawal.
It is desirable that the tissues be packaged in quantities of about one hundred or more per container. An interfolding machine of the type employing principles described in the Marcalus et al patent would require enormous size and complexity in order to provide a bundle of such a large number of tissues. Such a machine would give rise to untold scores of problems concerning cost, space, maintenance, etc.
It has also been found that the rapid drawing of endless webs of paper across components of the folding assembly can produce friction and other binding which can lead to damage of the webs.
It is, therefore, an object of the present invention to provide a compact and convenient system for interfolding large numbers of paper webs.
It is another object of the present invention to provide methods and apparatus for interfolding the tissues of separate bundles of paper webs.
It is a further object of the present invention for providing methods and apparatus enabling a plurality of interfolding mechanisms to be employed in series whereby the output of all the mechanisms can be combined to form a stack of interfolded webs of paper that can be used for facial tissues and the like.
It is yet another object of the invention to provide a folding assembly for interfolding webs into a bundle which minimizes binding and yet which provides the required degree of tautness of the webs.